Cultured chick sympathetic neurons: ATP-induced noradrenaline release and its blockade by nicotinic receptor antagonists

The ATP-induced increase in tritium outflow from cultured chick sympathetic neurons prelabelled with [³H]-noradrenaline was investigated.Seven days-old dissociated cell cultures of embryonic paravertebral ganglia, loaded with [³H]-noradrenaline (0.05 M), were superfused in the presence of (+)-oxaprotiline and exposed to ATP, ATP-analogues, or 1,1-dimethyl-4-piperazinium (DMPP) for 2 min. ATP (3 LM-3 mM), 2-methylthio-ATP (3–100 M), as well as DMPP (10 and 100 M) induced a significant overflow of tritium. The EC₅₀-value of ATP was 20 M. Both the ATP-induced and the DMPP-induced tritium overflow was Ca²⁺-dependent and sensitive to tetrodotoxin (0.3 M) and -conotoxin (0.1 M); in addition, it was inhibited by the ₂-adrenoceptor agonist 5-bromo-6-(2-imidazoline-2-ylamino)-quinoxaline (UK-14,304; 1 M). The effects of ATP and DMPP were not additive. The ATP-induced as well as the DMPP-induced overflow of tritium was diminished by the P₂-purinoceptor antagonists suramin (300 M) and reactive blue 2 (3 M); in all 4 cases, the inhibition amouted to approximately 40%. The tritium overflow induced by ATP or DMPP was almost abolished by the nicotinic receptor antagonist mecamylamine (10 M) and markedly inhibited by hexamethonium (100 M). Neither ATP nor electrical stimulation caused an overflow of tritium from cultures loaded with [³H]-choline.The results suggest that ATP at molar concentrations induces noradrenaline release from cultured chick sympathetic neurons via an action on a subclass of the nicotinic cholinoceptor.     

Erbliche Ursachen und Risikofaktoren der Alzheimer-Krankheit

A multifactorial etiology underlies the majority of cases of Alzheimer's disease (AD). Both ill-defined environmental and genetic factors contribute to the development of the disease. Allele epsilon 4 of ApoE is a genetic risk factor. Its presence increases the risk of developing AD. However, presence of e4 is neither necessary nor sufficient for the disease to arise. Apart from the common multifactorial forms of the disease, there are rare variants which are inherited as Mendelian traits. To date three genes are known that can be mutated in these rare forms of AD. Of these, mutations in the gene presenilin 1 on chromosome 14 are most frequent. In addition, mutations in the gene presenilin 2 on chromosome 1 and in the amyloid precursor protein gene (APP on chromosome 21) occur in autosomal dominant AD. This article reviews our present knowledge of the genetics of AD and discusses its relevance for patients with AD and their relatives.     

Rooming-in-Modell Beeinflußt die Mitaufnahme bzw. Nichtmitaufnahme der Mütter den Krankenhausaufenthalt von Kleinkindern?

Zahlreiche Studien best?tigen insgesamt die st?rungspr?ventive Eigenschaft des Rooming-in. Die vorliegende Untersuchung besch?ftigt sich vor allem mit der Frage, für welche Gruppe von Kindern, bei Inanspruchnahme des Rooming-in bei Krankenhausaufenthalten Vorteile zu erwarten sind.     

Pharmacologic and Pharmacokinetic Assessment of Anti-TGFβ2 Aptamers in Rabbit Plasma and Aqueous Humor

Purpose The aim of the study is to determine the bioactivity and effects of PEGylation on the pharmacokinetics in rabbit aqueous humor and plasma of an aptamer directed against TGFβ2. Methods Pharmacological activity of anti-TGFβ2 aptamer in rabbit ocular fluid was demonstrated using a mink lung epithelial cell proliferation assay. For pharmacokinetic analyses, concentrations of aptamers in plasma and aqueous humor were determined over time following bilateral subconjunctival administration to Dutch-belted rabbits using a hybridization-based pseudo-enzyme-linked immunosorbent assay (ELISA) assay. Results Anti-TGFβ2 aptamer (ARC81) binds to human TGFβ2 with a K_D of approximately 5 nM and inhibits the activity of human TGFβ2 in vitro in a cell-based assay with an IC₅₀ of approximately 100 nM. ARC81 blocks endogenously derived TGFβ2 in rabbit aqueous humor in vitro with an IC₅₀ of approximately 200 nM and an IC₉₀ of approximately 1 μM. In vivo in rabbit, ARC81 [no polyethylene glycol (PEG)] entered systemic circulation rapidly (t_max = 1 h in plasma) relative to aptamer conjugates ARC117 (20 kDa PEG) and ARC119 (40 kDa PEG), which showed prolonged residence in the subconjunctival space and aqueous compartment (t_max = 6 and 12 h, respectively, in plasma). Both 20- and 40-kDa aptamer conjugates reached maximal concentrations (C_max) in aqueous humor of 23–30 nM and remained at or above 1 nM for as long as 12 h. Conclusions Pharmacologically active levels of anti-TGFβ2 aptamers can be sustained in the ocular fluid and local tissue environment over a 12-h period after single administration. Daily subconjunctival administration of PEGylated anti-TGFβ2 aptamers should allow further pharmacological evaluation of these agents in a rabbit conjunctival scarring model. Perioperative administration, via subconjunctival injection, may prove to be an effective means to deliver therapeutic quantities of TGFβ2 aptamer conjugates in trabeculectomy procedures.     

Prediction of individual clinical outcome in MCI by means of genetic assessment and (18)F-FDG PET.

Patients with mild cognitive impairment (MCI) represent a risk population for progressing to dementia of the Alzheimer type (DAT). However, clinical criteria do not ensure reliable individual prognosis in these patients. The objective of this longitudinal, prospective study was to examine the value of (18)F-FDG PET of cerebral glucose metabolism and of genetic susceptibility, as defined by an APOEepsilon4-positive genotype, with regard to the early diagnosis of DAT in patients with MCI. METHODS: In 30 patients with the diagnosis of MCI (16 female, 14 male; age, 70 +/- 8 y), baseline and follow-up examinations (mean observation period, 16 mo) were performed. In all patients, the APOE genotype was assessed and cerebral glucose metabolism was evaluated at baseline using cranial (18)F-FDG PET. Individual PET data were screened for findings suggestive of Alzheimer's disease (AD), with the help of an automated computer program. After stereotactical normalization of the PET images, this program performs an observer-independent statistical comparison with an age-matched reference database (n = 22). RESULTS: In 43% of all MCI subjects, a PET scan suggestive of AD pathology according to our predefined criteria was observed at baseline (PET+); 57% of all MCI patients were carriers of the APOE epsilon4 allele (e4+). In 40% of all patients, progression of symptoms within the observation period justified the clinical diagnosis of probable DAT at the time of follow-up reevaluation. Statistical evaluation revealed the best results for PET with regard to early diagnosis of DAT in MCI patients (sensitivity, 92%; specificity, 89%). Classification according to the APOE genotype was significantly less successful (sensitivity, 75%; specificity, 56%). However, a combination of both diagnostic tests allowed early diagnosis with either very high specificity (PET+ AND e4+: sensitivity, 67%; specificity, 100%) or very high sensitivity (PET+ OR e4+: sensitivity, 100%; specificity, 44%). CONCLUSION: (18)F-FDG PET of cerebral glucose metabolism is a valuable diagnostic tool for the prediction of clinical outcome in individual MCI patients. Results are superior to the exclusive assessment of the APOE genotype. A combination of both functional imaging and genotyping may allow an early high-risk or low-risk stratification of patients with either very high sensitivity or very high specificity. This may be valuable, for example, for patient selection in scientific studies.     

基于批判性思维的综合护理在老年冠心病合并高血压患者中的应用评价

目的:基于批判性思维的综合护理在老年冠心病合并高血压患者中的应用评价.方法:选取2018年11月—2020年1月于河南科技大学第一附属医院就诊住院的92例冠心病合并高血压老年患者,按随机数表法分为观察组和对照组,每组各46例.对照组予以常规干预护理,观察组应用基于批判性思维的综合护理模式干预.观察两组情绪变化、血压变化及治疗依从性.结果:干预后,观察组负性情绪评分均低于对照组(P<0.05);观察组血压控制情况优于对照组(P<0.05);观察组治疗依从性高于对照组(P<0.05).结论:基于批判性思维的综合护理干预可减轻老年冠心病合并高血压患者的负性情绪影响,患者血压控制更理想,治疗依从性更高.     

Autologous blood donation for surgery in inflammatory bowel disease--a report of six cases

BACKGROUND: Surgery in inflammatory bowel disease (IBD) is frequently associated with need for perioperative blood transfusions carrying the potential risk of infection. Autologous blood donation is often limited by IBD-associated anemia which is reversible by intravenous iron and erythropoietin. We therefore tested the feasibility of autologous blood donation in IBD. METHODS: Six patients (five Crohn's disease, one ulcerative colitis) with indication for elective bowel resection were treated after informed consent was obtained. Two to four blood donations were scheduled during four weeks prior to surgery. Once a week 350-450 ml of blood were collected from patients with a hemoglobin level above 11.0 g/dl. After each donation 200 mg of iron saccharate diluted in 0.9% saline were given to all patients intravenously as substitute for donation-related iron loss. Patients with preexisting anemia or C-reactive protein above 2.0 mg/dl received concomitant erythropoietin. RESULTS: The scheduled number of packed red cells was donated successfully by four patients. Due to low hemoglobin levels two patients donated one unit less than intended. Four patients received autologous blood transfusions intra- or postoperatively. No patient needed homologous blood. No serious adverse events were observed during blood donations, perioperatively, and during the one year follow-up period. CONCLUSION: Preoperative autologous blood donation is save and feasible in IBD patients with elective bowel resection.